Capacitor’s dielectric

V0

Symbol that represents the voltage value of the capacitance when there is no dielectric placed between the Capacitor plates

V = (1/κ)*V0

The relationship of the new voltage of the capacitor with a dielectric with the dielectric

Dielectric constant (κ)

A positive number greater than 1, characteristic of the material, that describes how much the dielectric reduces the voltage.

C0

Symbol that represents the capacitance of the capacitor when there is no dielectric between the plates of the capacitor

Q0

Symbol that represents the charge value on the plate before and after the insertion. (Insertion of the dielectric does not has any effect on the charge value)

C = Q0/V = (Q0)/(V0/κ) = κ(Q0/V0) = κC0

Equation to find the capacitance of the capacitor with a dielectric.

1

The dielectric constant of the vacuum

Stud

A vertical piece of wood or metal inside a wall that helps support the wall and holds up the panels or boards on the outside.

Gypsum

A soft sulfate mineral which is widely used in the construction for interior walls and ceilings due to its versatility, fire resistance, and sound insulation properties.

Mainly composed of calcium sulfate dihydrate (CaSO4•2H2O)

capacitor

The metal plates in an electronic stud finder function like a _________.

Stud finder’s operation

The stud finder device is placed flat on a wall and moved horizontally to detect the changes beneath the surface.

capacitance

When the finder passes over a wooden stud, the ___________ changes because wood has a different dielectric constant than gypsum;

Affecting the capacitance of the stud finder plates.

Stud detection

The change in the capacitance that triggers the circuit signal indicating the presence of a stud.

U0

Symbol that represents the energy stored by the capacitor with no dielectric

U = (1/2)*(Q^2/C) = (1/2)*(Q0^2/κC0) = (1/κ)*U0

Complete equation to find the energy stored inside the capacitor with a dielectric

electrical field

When a dielectric sample is brought near a charged capacitor, it reacts to the ________________ of the capacitor plates.

polarization

Surface charges appear on the dielectric due to the ____________, but they are not free charges like the ones in the conductor.

opposite, attract, dielectric

The dielectric develops surface charges that are ________ in signs to the charges on the capacitor plates.

These charges _______ each other, pulling the __________ towards the plate.

polarize, stored electrical energy

The work is done to ________ the dielectric, and this comes at the expense of the capacitor’s ________________________

2.1

What is the dielectric constant of the Teflon^TM?